A fluid permeable member is configured to allow a fluid (a gas or a liquid) to pass through and is used for the purpose of diffusion, separation, purification, filtering, analysis, reaction, or the like of the fluid.
In general, a large number of fluid permeable holes are formed in the fluid permeable member. In order for a fluid to pass through the fluid permeable member and to be uniformly distributed, it is preferable that the inner width of the holes is small and the number of the holes is large. However, from the viewpoint of manufacturing, many difficulties are involved in forming the holes to have a small inner width.
As an example of the fluid permeable member described above, there is known a diffuser (shower head) that uniformly distributes a gas on a glass plate disposed in a vacuum chamber for manufacturing a liquid crystal display (LCD) or a semiconductor wafer. The liquid crystal display (LCD) is a non-light-emitting element that obtains an image effect using the characteristics of a liquid crystal injected between an array substrate and a color filter substrate. Each of the array substrate and the color filter substrate is manufactured by depositing, patterning and etching a thin film, several times, on a transparent glass plate made of a material such as a glass or the like. In the case where a deposition process is performed by introducing a reactive material and a source material into a vacuum chamber in a gaseous state, the introduced gases pass through a diffuser (shower head) and are deposited on a glass plate mounted on a susceptor to form a thin film.
A diffuser (shower head) as the aforementioned fluid permeable member is disclosed in Korean Patent No. 0653442.
As shown in FIG. 1, a reaction gas introduced through an introduction part 18 passes (permeates) through a diffuser 15 and is injected onto a glass plate or a wafer mounted on a susceptor S.
However, the conventional diffuser has a problem in that the holes formed in the diffuser cannot uniformly inject the reaction gas onto the glass plate. In an effort to ameliorate this problem, it is conceivable to adopt a method of reducing the inner width of the holes and increasing the number of the holes. However, this method has a limit from the viewpoint of manufacturing.